The present invention relates to data communication devices, personal handy-phone system base stations, and methods of communicating data.
The benefits of a wireless communication network are readily recognized. The ability to transmit and receive either voice or peripheral (i.e., facsimile) messages in mobile environments has been utilized in numerous applications.
Wireless communications systems including cellular systems have enjoyed increasing popularity. Cellular systems generally comprise a base station and a plurality of portable stations. Cellular systems offer a radius of approximately 1-15 km per base station, and traditionally provide coverage for cities, railways and main roads. Existing cellular systems typically utilize a service network which is distinct from the existing traditional telecommunications network.
Other wireless communication protocols have been introduced to provide benefits over existing cellular wireless technologies. Such communication protocols provide benefits of interfacing directly with and utilizing the existing telecommunication network. Such direct interfacing capabilities eliminate the need for a distinct switching system.
One such communication system is the personal handy-phone system (PHS). The personal handy-phone system is a digital cordless telephone system that offers integrated telecommunication services, such as voice and data, via a universal radio interface. The personal handy-phone system offers digitalization of the communication system. In particular, the digital personal handy-phone system offers improved quality and effective use of frequencies. The personal handy-phone system also offers flexible inter-connectability wherein connection of a personal station with a plurality base stations at various locations such as the office, home, or outdoors is possible. The PHS standard is set forth by the Telecommunications Technical Committee of Japan in xe2x80x9cPersonal Handy-Phone Systemxe2x80x9d, Japanese Telecommunications System Standard, RCR-STD 28.
The personal handy-phone system also offers connectability with existing communications networks. Connection is possible with analog telephone networks as well as digital networks, such as an Integrated Services Digital Network (ISDN) communication platform.
Personal handy-phone systems typically comprise a plurality of personal or portable stations (PS), also referred to as handsets, and base stations, also referred to as cell stations (CS). Personal handy-phone systems are designed to provide wireless multimedia communications, terminal mobility, and complete two way communications. Personal handy-phone systems utilize a micro-cell structure. Personal stations and base stations of the personal handy-phone system are configured to transmit and receive data via a plurality of data packets, also referred to as PHS slots.
Data may be transmitted in a PHS system at either a half rate or a full rate according to the PHS standard. Half rate communications provide digital communications at a bit rate of 16 kbps (kilo bits per second), while full rate communications provide digital communications at an increased bit rate of 32 kbps.
The base stations of the wireless system are coupled with the telecommunication networks in typical configurations. Integrated Services Digital Networks present bearer channels, also referred to as B channels, and a delta channel, typically referred to as a D channel. ISDN basic access provides two bearer channels and a single delta channel and may be implemented along a traditional twisted pair of copper cable. ISDN primary access provides thirty bearer channels and a single delta channel and may be implemented along a single coaxial or fiber optic cable.
The bearer channels provide transmission of user data between interfaces at a bit rate of 64 kbps without altering the transmitted data. The delta channel provides transmission of packetized signalling or control information, such as dial up information, between a user and a local exchange at a bit rate of 16 kbps. Despite the increased transmission capabilities of existing telecommunication networks, some standards, including PHS, provide for the insertion of xe2x80x9cdummyxe2x80x9d data to provide communications at increased rates. For example, in PHS, four dummy bits are added to four bits of full rate PHS data to provide the PHS data at a bit rate of 64 kbps. Alternatively, six dummy bits are added to two bits of half rate PHS data. Currently, the dummy bits do not communicate useful information.
In light of the above, there exists a need to provide improved interfacing between wireless communication systems and associated communication platforms to provide full utilization of the transmission capabilities of the platforms and maximum data transfer.